Hi W.V.J; I became intriqued by your choice of the 47 tube as I remmembered I had an old article in Radio Craft Magazine that explains a nice SE direct coupled 47 tube amp. It seems pretty easy to build but uses a 56 or 27 driver tube and it is choke coupled. It is a 5 page breakdown of the amp with schematics and description. Very thorough. If interested it is too much to put on this site so should you like e-mail me and I can scan a copy to you. J.R.